Reasons for Identical and Fraternal Twins


Types of Twins in Hindi

Video taken from the channel: Sandip’s Biology


Formation of Twins

Video taken from the channel: Claudia Chen


Fertilization and Implantation, Identical twins and Fraternal twins

Video taken from the channel: MedKes TF IND Medical and Health


Identical Twin Formation-First time ever witnessed The Cleavage of a Blastocyst

Video taken from the channel: Rasverix Xyleighraq


In the Womb Identical Twins

Video taken from the channel: Naked Science


Learning about Multiple Pregnancy

Video taken from the channel: All Health TV


Differences between identical twins and fraternal twins. Multiple pregnancy

Video taken from the channel: Instituto Bernabeu

The other name for fraternal twins is dizygotic twins, meaning two fertilized eggs. They’re the result of the mother releasing two eggs at the same time with each egg being fertilized by a. Mirror twins always come from a single fertilized egg and share the same genetic makeup.

That said, the exact cause of the mirroring in some twin pairs is. History of twins: Once you have a set of fraternal twins, you’re twice as likely to have another set in future pregnancies. Number of pregnancies: The more pregnancies you’ve had, the greater your chances of having twins. Race: Twins are more common than average among white and African American people and less common amon Hispanic and Asian people. Identical twins are the same sex as each other and look very alike.

Nonidentical, or fraternal, twins: This type of pregnancy occurs when there are two eggs present in the womb at the time of. Because fraternal, or dizygotic, twins are 2 separate fertilized eggs, they usually develop 2 separate amniotic sacs, placentas, and supporting structures. Identical, or monozygotic, twins may or may not share the same amniotic sac, depending on how early the single fertilized egg divides into 2. A pair of a twin can either be monozygotic or dizygotic.

In the monozygotic twin, they are identical as they develop from one zygote. Whereas, in dizygotic, the twins split and form two embryos and are ‘non-identical’ or called ‘fraternal.’ It means that each twin develops from a separate egg, with each egg being fertilized by its sperm cell. 6. Advancing maternal age. Women who are aged in their 30’s and 40’s have significantly higher chances of conceiving with twins.

Younger women, especially those aged in their 20’s, do not have as much chance. Having assisted reproductive technology, in particular taking medication which increases ovulation. Most of the time, the cause of MZ twinning is unknown. Dizygotic (DZ) twins, also called fraternal twins, occur when two egg cells are each fertilized by a different sperm cell in the same menstrual cycle.

DZ twins are about twice as common as MZ. To form identical or monozygotic twins, one fertilised egg (ovum) splits and develops into two babies with exactly the same genetic information. To form fraternal or dizygotic twins, two eggs (ova) are fertilised by two sperm and produce two genetically unique children.

Non biological twins.

List of related literature:

Either a single fertilized egg divides to form two genetically matching organisms, which then become identical twins, or two eggs are released approximately simultaneously, and a different sperm fertilizes each, resulting in fraternal twins.

“Social Work Perspectives on Human Behavior” by Margarete Parrish
from Social Work Perspectives on Human Behavior
by Margarete Parrish
McGraw-Hill Education, 2014

Identical twins have identical genes, so they should also have the same susceptibility to hereditary diseases; whereas fraternal twins (which originate from two separate, fertilized eggs) have no greater similarity in their heredity than brothers or sisters born at different times.

“Foods & Nutrition Encyclopedia, Two Volume Set” by Marion Eugene Ensminger, Audrey H. Ensminger
from Foods & Nutrition Encyclopedia, Two Volume Set
by Marion Eugene Ensminger, Audrey H. Ensminger
Taylor & Francis, 1993

It is sometimes difficult to determine by ultrasound or at birth whether twins are identical or fraternal because the two fraternal placentas may fuse and appear as one large placenta.

“Maternal & Child Health Nursing: Care of the Childbearing & Childrearing Family” by Adele Pillitteri
from Maternal & Child Health Nursing: Care of the Childbearing & Childrearing Family
by Adele Pillitteri
Wolters Kluwer Health/Lippincott Williams & Wilkins, 2010

Recent studies in humans of identical (monozygotic) and fraternal (dizygotic) twins have shown that the effect of sharing the same placental milieu adds to that of sharing the same genes (Kaminsky et al., 2009).

“What Darwin Got Wrong” by Jerry Fodor, Massimo Piattelli-Palmarini
from What Darwin Got Wrong
by Jerry Fodor, Massimo Piattelli-Palmarini
Profile, 2011

Early research focused on 15 pairs of identical twins (monozygous; same heredity from a single fertilized ovum) and 15 pairs of fraternal twins (dizygous; like ordinary siblings, derived from two separate fertilized ovum) raised in the same city and with parents of similar socioeconomic backgrounds.

“Exercise Physiology: Nutrition, Energy, and Human Performance” by William D. McArdle, Frank I. Katch, Victor L. Katch
from Exercise Physiology: Nutrition, Energy, and Human Performance
by William D. McArdle, Frank I. Katch, Victor L. Katch
Lippincott Williams & Wilkins, 2010

When genetic influences are entirely additive, the similarity of identical twins (raised apart) is about twice that of fraternal twins (raised apart), because identical twins have twice as many genes in common as do fraternal twins.

“Individual Differences and Personality” by Michael C. Ashton
from Individual Differences and Personality
by Michael C. Ashton
Elsevier Science, 2013

Fraternal twins resulting from eggs that are fertilized at the same time but that are not identical.

“Comprehensive Dictionary of Education” by Maqbool Ahmad
from Comprehensive Dictionary of Education
by Maqbool Ahmad
Atlantic Publishers & Distributors (P) Limited, 2008

Causes: Monozygotic twins result from the cleavage of a single fertilized ova (4/1000 births).

“Netter's Obstetrics and Gynecology E-Book” by Roger P. Smith
from Netter’s Obstetrics and Gynecology E-Book
by Roger P. Smith
Elsevier Health Sciences, 2008

The tendency for fraternal, but not identical, multiple births seems to be hereditary.

“Memmler's Structure & Function of the Human Body, Enhanced Edition” by Barbara Janson Cohen, Kerry L. Hull
from Memmler’s Structure & Function of the Human Body, Enhanced Edition
by Barbara Janson Cohen, Kerry L. Hull
JONES & BARTLETT PUB Incorporated, 2020

Because these twins habitually are fraternal (two separate eggs fertilized by separate sperm), it is a possibility that twin offspring of the opposite sex share the same placenta.

“Primate Anatomy: An Introduction” by Friderun Ankel-Simons
from Primate Anatomy: An Introduction
by Friderun Ankel-Simons
Elsevier Science, 2010

Oktay Kutluk

Kutluk Oktay, MD, FACOG is one of the world's foremost experts in fertility preservation as well as ovarian stimulation and in vitro fertilization for infertility treatments. He developed and performed the world's first ovarian transplantation procedures as well as pioneered new ovarian stimulation protocols for embryo and oocyte freezing for breast and endometrial cancer patients.

Mail: [email protected]
Telephone: +1 (877) 492-3666

Bibliography: oktay_bibliography

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  • Twins are siblings NOT meant for marriage. Therefore the idea of twin relationships is flawed. Friends yes, relationship = BIG no.

  • I’m a quadruplet
    Ok so all 4 of us started as 3 different eggs so we were supposed to be fraternal triplets but my egg decided to split and now were quadruplets and I have a identical twin sister
    Fun right
    Probably not for my mom

  • I think that being gay or straight is about personality, like you liking yellow or pink more. You can’t choose to like yellow over pink, it’s something that just happens and comes with your personality, which is both genetic and environmentally formed. So yeah, I think it’s both. Some twins share some personality traits like both being shy, being good singers, liking sports. while some they don’t. With sexuality attraction, I think it’s the same. Both genetic and environmental. I have two gay uncles and my dad is the only straight one. All raised in the same environments. We are all different, even identical twins.

  • I’m only watching this cause I’m a twin and I wanna learn more �� but I’m a girl and my twin is a boy (but we’re not identical we’re fraternal twins) and tbh I’m kinda glad im twin cause All my friends are always saying I’m lucky to be a twin ❤️ me and my twin brother do everything together and go almost everywhere together. And me and him always had the same classes for school untill this year…..�� me and him now have all separate classes and it’s kinda weird for me now:(

  • I have an identical twin sister. We were born in 1965 at 7 months and are 2 minutes apart. We weighed 3 pounds and something ounces. We looked identical growing up, but once she had children our characteristics changed. We are 5’4 and I weigh 122 pounds and she weighs 170.

  • 2:56 So the only answer to why this happens is because of the weakening of the junction between the cell and the trophoblast membrane, which causes the cell to repair and split in two to form a new identical cell…I’m thinking about how skin cells repair themselves. Well I’m not a specialist so I might be wrong but that’s just my hypothesis. I took biology in 10th grade ��

  • Wow, this video is so detailed. Shows exactly how the blastocyst are formed. Am actually taken aback by the graphics. Many couples trying to conceive hope to have twins. Their reasons vary. From ensuring that their child has a close sibling through childhood to simply wanting a large family. While multiple births occur in about 3 percent of all pregnancies in the United States each year. Experts say there are some steps women can take to increase their chances of having twins. Diet, ethnicity, genetics and lifestyle all play a role in whether a woman is more apt to have twins. I can also add artificial means. That is like IVF. I have some friends who went through IVF in Bio tex clinic. And the amazing part is that more than half are mothers to twins. However, there are other methods of conceiving twins than IVF. Both natural and artificial.

  • I have and abdominal pregnancy that have not been proven and I can’t wait to get this baby out of me so that I can start having another baby with the love of my life my boyfriend he’s so special to me he’s loving and kind and so much more plus we both want a big family and we will in Jesus name amen

  • Hi.. �� this is Irwan and Erwin, and we are Twins, I’m Erwin the youngest. And I’m so blessed that I have Irwan as the older Twins brother.

  • I ordered from Dr Odin Herbal Home. Please I sincerely want everyone to try this herbal medicine because it has given me back my life. My test results were received and it came back negative after having this virus herpes for several years. Let’s resend it to save the world and get everyone out of the pharmacy cage. You can contact Dr Odin at [email protected] or whatsap +2348139424847

  • I have fraternal twins one boy and one girl they are different and their tastes are also different now they are 7 years healthy by god’s grace but one problem occurred in my son as we found he has less vision and need to wear specs after few months we found that my girl is Also having less vision I am really worried ��

  • I’m an identical twin and my sister and Myself are completely different. She’s a bully and religious control freak. She is manipulative and married a bully. She has had a major negative detrimental impact on my life. I still love her but she has GREAT DELIGHT in bringing me down?We were so close as youngsters. Heart breaking. ��

  • If sexuality turns out to really be genetic and confirmed before birth, that would debunk the common claim that gay people “choose to be gay.”

  • Sexual orientation is not genetically marked… I am a heterosexual male, happily married to my soulmate and we’ve been blessed with two beautiful rowdy sons and one lovely little princess…

    My identical brother is gay… even he says it’s a decision issue, not genetic or how he was raised… he was bi-curious at 14 and decided to bat for the other side once he got the taste of that lifestyle… nonetheless, he will always be my brother who will always be a major part of my life…

  • Me and my brother are the only surviving twins in our whole family history, for some reason every other pair of twins in my family circle die either after birth or before birth so I’m scared because what if our deaths are just delayed

  • My identical boys implanted differently in the same placenta… it so funny because the bigger twin, who had better rooting (blood supply)!still has a crazy appetite vs his brother!

  • I’m 18 weeks pregnant with non identical twins I’m so blessed �� my mother had non identical twins 28/9)1994 boy girl my due date is 28/9/2019 2boys to me this is a miracle ����

  • I have a twin sister and we are always together and we buy the same clothes and i love her so much (its like i have 2 souls.. shes my second soul) i thank god so much because i feel lucky to have her ❤❤

  • I have a question for everyone.

    Which would you rather have: an identical twin or an fraternal twin?

    I would rather have an identical twin, since fraternal twins are pretty much just regular siblings that are just born about the same time.

  • I am asking God whenever my time is come to have children I’m begging him to give me two identical twin daughter and ask him please let their born with good health

  • Those nannies in the womb are alive from conception! How can anyone abort them saying otherwise! They feel the pain when ripped from the mother’s womb!!!

  • The best video i have seen explaining why being gay is not a life style choice and is decide before birth in the womb -similarly why some people are left handed and some right handed

  • It must be great to have a twin, having a very unique bond with someone that’s another you. You’ll always have a “partner in crime” too.

  • I have one question.Is it possible for the 2 first formed cells of zygote to develop into 4 cells by dividing mitotically at the same moment and at the same second?

    Can anyone answer this.please help with legitimate answer

  • By the way, sperm are NOT motile until they are capacitated within the uterus. This step was essential to discover in order to enable the development of In Vitro Fertilization

  • The fetuses pictures they are showing are of fraternal twins not of identical twin… identical twin are in one sac sharing one placenta

  • It is a mystery. God knows only why it splits. Some things can’t be explained just accepted. Science is fascinating. God is wonderful

  • Kabhi _2 ye bhi hota h ki dusare baby ko yk ghante Baad nikale ya 4 ghante Baad Aisa kyo hota h to pehla jo baby nikala h mar nhi jayega

  • When semi-identical twins are born, are there any diformity, health issues for one of the twins? Because I remember reading years ago that when there is identical twins of different sex, usually the girl twin is sterile and had health issues!

  • I’m gonna go ahead and clear this up for all the people being pissy in the comments.

    When he says mistake, he does not mean the resulting two people are a mistake. What he means is that the cell makes an error in dividing, resulting in two people. It’s true that nobody knows what causes this mistake to occur, but it is by definition a mistake. The literal definition of mistake is error, which is what happens during embryonic cell division to cause identical twins.

  • 32 yrs ago I was lucky enough to have a healthy set of twins. Birth weights were 7 lbs 3 ounces, 21″ long and 4 lbs 11 ounces, 18″ long.